Dampening Material

[mattkinsey]

I'm building the cynosure and was wondering if carpet padding would make a good dampening material or should I stop being cheap and by PE's Sonic Barrier. Also does anyone know if regular spray paint clear enamel would be good to seal the copper side of a PC board.
(Why do I find myself on this site every night?)

[scottc]

Sandwich a layer of vinyl floor tile between two layers of carpet padding, and you begin to get some damping - a single 1/2" layer doesn't offer much

[mattkinsey]

> Sandwich a layer of vinyl floor tile between
> two layers of carpet padding, and you begin
> to get some damping - a single 1/2"
> layer doesn't offer much
So you think I would be better off with Sonic Barrier?

[scottc]

> So you think I would be better off with
> Sonic Barrier?
Absolutely, and supposedly Black Hole 5 is better still (and pricier!) It is simply a matter of how much you want to spend.

[Deward Hastings]

Two very different materials worth a look, depending on what you want to damp, are Auralex Sheetblok (best to stop transmission through panels or panel vibration) and rigid mineral wool (4lb or 8lb per cu ft), best for sound absorbtion (as in bass traps). Both are substantially better than the best acoustic foam. You need to decide just what it is you want to "damp" to select the appropriate material/application.

Sheetblok is not cheap, rock wool rigid insulation is, but it comes in rather large bundles, so it's hard to buy just what you'd need for a couple of speakers. Use the excess to tune your room . . .

[matg]

if you are looking for just cabinet fill, to stop the hollow box sound, then cheapo polyfil or fiberglass will do the trick. If you have to stop panel resonance/vibrations, you need to stiffin/brace your cabinet better. The cynosure should not be putting out the kind of low freqs. that would really excite a 3/4" or 1/2" panel with much force. if it is, brace, brace, brace.

as for the PC board, if you need to seal to stop oxidation, yes, basic clear spray enamel will work, as will clear spray lacquer. just be sure it is totally dry before you send any power through the board. You can also use spray plasti-dip in clear. more of a rubber consistancy and probably better electrical insulating qualities.

'm building the cynosure and was wondering
> if carpet padding would make a good
> dampening material or should I stop being
> cheap and by PE's Sonic Barrier. Also does
> anyone know if regular spray paint clear
> enamel would be good to seal the copper side
> of a PC board.
> (Why do I find myself on this site every
> night?)